Road grading apparatus



Aug. 29, 1933. H. H. SAMUEL 1,924,572

ROAD GRADINGl APPARATUS Filed Jan. 13, 1932 3 sheets-sheet 1 Aug. 29,1933. H. H. SAMUEL ROAD GRADING APPARATUS Filed Jan. 13. 1932 3Sheets-Sheet 2 IN VEN TOR /f/z/eZ,

wwf/fi @a ATTORNEY I Aug. 29, 1933. H, SAMUELl RoAn GRADING APPARATUSFiled Jan; 13. 1.932 3 Sheets-Sheet 3 INVENTOR f Bwa/x/ A52/Mael,

' ment, be Vmaintained throughout the gradingop-A `eration at the properlevel to assure the 'exacty Patented VAug'.Y 2 9, 1933 Thisinventionrelates 'to improvements 1in road grading machinery;, 4and theinvention has`r referencermore particularly,l `to a novel construe` ytion of machine especially adapted `for-the nal preparation .of theAsubgrad'el of -roadways pre.- paratory to laying concrete pavementthereon` This vinvention has :for its, principal objectto provide anovelroad subgrader having selectively usable scarifying` means andscraping'j4 means,

both said'- means beingadjustable,fordepth of cut; and, furthermore; thesubgrader is provided .witha novel construction ottiactionrmeansdesigned to run on the metal forms,v as laidtolreceive castconcreteslabs of pavement, in such manner `that both the scarifyingl vmeans ,fand scrapingmeans may, `when set `fora given adjustdepth of cut, wherebyajnniform evenjdepthof grade willbe established and thereby `anexact andcorrect thickness of concrete slab produced, when the concrete mixiscast upon the prepared subgrade and between theside forms.

This invention has for a further objectto p roi Videja a novelconstruction of subgrader of 'the f ylind and for the purposesl abovementioned,

- whichlmaylbe' operated by drawingthe same `with( aroadrcilingmachine,so that/'grading androll-A ingcan be accomplished-inoneoperation` v dsingle operator.

more particularly enumerated, will be understood ,from the followingdetaileddescriptionthereof.A

Anillustrative embodiment of thisinventon is shown in the accompanyingdrawings? inl Figiis a fronteievatin ff nie novi suba grader accordingto this vinventionas operatively mounted to run on concrete castingforms, and* f as arranged for the use and operation lofl the tscarifying means thereof Fig,\2 is asimilar irview, ,i

A Handvmounted, adjacentftofeither Ithe innr; orf'` oute'rsides of `saidchassislbeams; according 4 tog showing `the subgrader as arranged forthe `use and operation p of the scraping means thereof; Fig is averticallongitudinal section, taken on line 3- `-,f-3 `in Fig.` 2; and 'Figl Athe subgrader apparatus;V

Fig. 5 is a detailviewi in part sectionlshowing one ofthe adjustablelateral guide rollers of the machine which cooperate with the concretecast-` ing forms, and whi h V serve to hold the, machine,

L when;Y operated; vagainst lateral i shifting y cir:l

placement relative tosaidforms; and Fig.61sa y 'detailhorizontalgsectionlo f'i he same, taken' 0n is a 4plan View` of .t

porting the machine from v job to jobgFigI 8 is a` deta'iljsideelevationfxoffa detachable journal elementand transport wheelwhichvfo'rm said detachable .traction means; and Figi. v9 is an exteriorend elevation ofy said Ajournal element/Similargcharacters-of!reference,,are employed X in .the above describedviews, te indivcatetcorref spending parts.

Referring I low to' the drawings, thefreference' character 1'0Yindicat'es the side chassistbeamstiof `the machine frame-work. tSecured to andgupon,l `and extending transversely between `said chassis'beams 10 at theiro'nt end ofthe. machineiare a `pairoi longitudinallyspacedbolster beams 11;

and arrangedinnige mannerfat the 4rearlend of n the machine is athirdbolster beamf 12. Secured `-toaxid vupon the bolster ,beams 115,and;12,'jand extendinglongitudinallyfrom-frontje, 'rearof l, -the Vmachineinafsubstantially centralposition is, aj;` bedgbeam 13, i- Similar'longitudinallubed" beams 14 are arranged invlaterally spaced relaAnother object of this invention is to .provi'c'lkia-l novelconstruction .of subgrader `having selec-1." f tively usable andadjustable scarifying-and scrap- A ing means so arranged that the samemay bercon?V trolled for bothj useand for `adjustment by` -a tion -ato yopposite sides of saidA f central' `bed beain Y transversely extendingbridgeybearn I15. `l 'I he various beams f above described constitutethe Y ylframe-'worlror carriage body. ofthefmachine,and'.v Other objectsof-this invention,V not at this time Si, 13. Secured toand upon saidbedbeams13=+1fi v adjacent to theA rear endjot the machine; isi-aA same iin assembled vrelationfby the processor vThe -cliassis bearnsfl'() areyrespectively pro- J 17, VSaid traction wheels l'lmaybet arranged theconditionsvV governing the particular job, as will besubsequently againreferredto. The tracvidedzadja'cent to their forward and,` rearward `Vends ',Wi.t11 bearing, members .1G--in Which-fer@ 1" :c

journaled'the axle portions fof tractiomwheels :100'

105L 'tici- 1 wheels areinitiallyfgauged or `transversely spaced apartYat distances tocorrespondto ,the

laterally spaced relationofv laid 'metallici concrete *1' s t, 091i' the,connection therewith of,detachabletraction-1 t j means with Iwhich thelsameiinay be provided,a nd g Vwhich serve vas a convenientmeans yfortrans-` 90 4.saidbearns may be. suitably securedtogetherby .c

4any suitable form of `f astenir-igv means; although j I have Afounditzvveryfsatisfactory to fastenthe`v building operationspwhereby thevmachine carriage or frame-work may laterally straddle'said forms,Vwhile being supported by thetraction wheels 17 for longitudinalmovement upon and ,along said forms. n

In order to prevent displacement of the framework'or carriage of themachine andthe traction wheels 1`7-thereof relative to the forms 18,

when Vmoved-"over and along the latter',V guidev means are mounted onthe frame-work ,orcar- `riage to engage and cooperate` with the innerfaces of therforms 18. One such guide -means is located adjacent to andinwardly of each trac-v tion wheel 17.l Each guide means comprises a`vertical shaft 19', whichis securely clamped to the ou'ter face of anadjacentbolster beam, 12'

or 13 as the case may be, by means of a U-clip '20, rwhich embraces'theshaft `19,-a'nd `the. legs of which pass through the body ofthefbol'ster'beam,-

whereby the same be ysecured to thelatter by nuts 21v which screw uponthefree' ends of 'saidlegsf The lowerend of the shaft 19 ispro,

vided with a.diametricallyenlarged lateral annular ange v22 (see Fig. 5)to support the lower ends Oria-plurality of anti-friction rollers 23disposed aroundthe llower end portion of the shaft.v YA guide roller 24is mounted on the lower end portion'of the' shaft 19 to freely rotatethere- 'on kand 'upon the.anti-friction rollers 23. `If

desired the lower open end ofthe guide roller 24 maybe closed byafbottomcover plate 25 suitably secured thereto, and which servestofk'eep dirt and other'fcreigny matter from; gaining ace vcess to theinterior of the'anti-friction `bearing elements-serving saidguideroller.A The flanges of the bolsterbeam, at the pointsrwhere aguideroller shaft A19 is connected "therewith, are-pro- 'vided with,indented semi-circular seats 26, and

the shaftl is provided with reducedportions 2,7 eccentricto the axisthereof. Said eccentric por-` tions V27 are engaged respectivelyfin theseats 26.

`{By' reason of this arrangementadjustments of the guide roller 124toward and-from the inner Yface of a vform 18 maybe easily :made byaxially lturning-the shaft inonedirectin or the other to Iturn theeccentric portions`27 inthe seatsf26,

Y' A thereby moving thefguide roller 24 inwardly or use will bearagainst the inner faces lof the forms straight-upon the" tops ofV the'forms, and the `machine properly centered over the' road surface'betweenvtheformskwhich is to begraded. The,

guide rollers 24 may bearrangedtobearr on the form faces at any desiredpoint/intermediate the I top-and 'bottomfportions of the-1atter.Ifarranged to'bear'lowI down on the form faces, that l The kind andstructural character of the forms themselves will readily indicate the*best point to'be'- engagedby the guide rollers 24.

rI he scarifying means of the machinefisflooated 'at the forwardend ofthe same, and lcomprises the following arrangement. Securedto' thebolr*sterbeauns 11', paralle'l to `andspaced inwardly from the1sidesAofthe outer bed beams 14 are angleirons 28, which together'with the bedbeams 14 and the spaced bolsterfbea'msA llprovidel ver tical guidewaysin which are ydisposed vertically movable carrier'members" 29. IIt ispreferabler *tofcutaway the :body of the Vcentral bed beam l' `carriermembers.

13 to provide a guideway for aV similarly 'arranged vertically movablecentral carrier member 29. Suitably'secured to the lower ends of saidcarrier members 29, so as to extend transversely of the machine, isaV-shaped holder compris-v ing the upwardlyand rearwardly inclinedbackplate 30 and the upwardly andforwardly inclined front-plate 31.Mounted upony the lupper outer surface of the latter, are a plurality oflaterally spacedscarifying teeth 32, having chamfered chisel-likeends-These teeth are 'reversible" end for end, and'can be removed from theholder, reversed -and reinserted therein when first vfused ends becometoo worn. Thek teeth are l rigidly held in secured'relation to theholder by means of a clamp-strap 33 adapted tooverlie the'upper endportions of,v the teeth, said clamp-'I housing 36 fixed on the centralbedbeam 13', is afshaft l37.1 Fixed'o'n'saidshaft 37 within the housing36 isaY segmental vor quadrant gear 38;l

Journaled in bearings 39 fixed 'on thewtop of said housing 36 isalongitudinal power shaft 40, the same extendingfrearwardly through a'plate 3010i said holder. Journaled in and exbed beams 14, and extendingthrough a central bearing 'standard 4l mounted on the vbridge 'beam` v15so that its rearwardend is located adjacent to Fixed von "the thel rearend' of the machine. Y rearwardend of said power shaft 40' isa hand.wheel 42`for manuallyapplying powerv thereto- Fixed on said'powershaft4l) is a worm 40 Iwhich engages-said segmental-or Quadrant gear V33,whereby power applied to shaft 40` in either direction is transmitted toshaft 37. 'Secured to said shaft 37 respectively adjacentto the outercarrier members 29 are leverv arms 43, thefree n ends ofrwhich areconnected by linl s44 .to said threaded into the angle irons 28 so as tolie Adjustable stop-screws 45 are in the path of downward swingingmovement of .12,0

said lever arms 45.A By adjusting the height' of -said Astop-screws45Itl1e'downward' movement of theecarrier members 29 Vandthe scarifying:means to be made by said scarifying means whenrlowered'w n to operativeposition.A v 13 so as to keep-thetractioniwheels"17 running Thescrap'ingmeans of the machine is' located fat the rearward end ofthe same,'andcomprises lthe following arrangement. Pivotally-connected Ybysuitablehinge knuckles 45 to the rearward bolster beam 11 are laterally spacedapart reari wardly extending carrierV arms .47 having down-.wardlycurved free ends. Suitablymounted onl the forward faces of thecurved free endsof.

said carrier `arms 47 to extend transverselyY of the machineis aconcavo-convexfscraper plate 48, with its concave faceforwardlypresented.

-Extending along ythe back Aof saidscraper plate is a reenforcingrib 49,which may bemade of angle iron welded or otherwise secured to thebody'of said scraper plate. Suitably ser'z'uredt'oV the lower marginalportion of'saidscraper plate is ajj toe-plate 50 -of `hardened steelvand having J its lower free working edge suitably sharpened. Secured to,and uponthe bridge beam"15 are laterally disposed'housings 51respectively outwardly .olf-set in opposite directions from thelongitudinal center of the machine. Each ,housling 51'is provided atitsupper end with spaced bearings 52 in which' is journaled a powershaft 53, having ahand wheel 54 on its inward end for manually applyingpower thereto. 'Mounted onpivoting shafts orn journals 55 extendingtrans# versely through said housings 51 are segmental o r quadrant gears(not shown) which are similar to the quadrant gear '38' of the abovedescribed scarifying means. These gears have outwardly projecting leverarms 55 4connected to move therewith. Fixed on each power shaft 53 is aworm 5'?V to engage and transmit to said quadrant gears the ,powerapplied to said shafts 53.- vThe pivoted` scraper plate structure isconnected at its opposite end portions by links 58 with the free ends ofthe respective lever 'arms 56. Connectedrefl spectively with oppositeVend portions' of :the

scraper plate structure are' upwardly projecting stop-rods`59, the "freeends of which slidably pass tion, and consequently the exact level ofther finished subgradesurface relative tothe tops of the forms may beassured, so that no waste occurs by casting any excessof concrete whenlaying pavement slabs thereof. Itvlill be observed that each end of thescraping means is individually controlled by its own raising andlowering means and itsY corresponding stop means, and.l consequently`the scraping Vmeans may be nicely adjustedl to produce subgradeshavinglateralpitch or declination for producing crowned pavement.`

'Securedto the' bolster beam 12 by 4brackets 62 is a platform 63 uponwhichy the operator of the machine may stand in order to! manipulate thehand wheels for selectively bringing `the scarify` ing and scrapingmeans into'and out of service, as may be required during the operationofthe machiner Y l The machine is adapted to be drawn during operationthereof by anysuitabledraft means, Preferably, however, the machineis`connected with a power 'graderoller as a 4trailer thereto, j wherebygrading and rolling may be accomplished 4 in one operation. A novelself-compensating coupling means ,isprovided which so functions .that yatrue straight pull upon the grading machinis assured regardless of anygiven path of travel taken by the hauling roller. This novel couplingmeans comprises a V-shaped draftyoke64, the respective arms of which arepivotally connected,

as at 65to the forward bolster beam 11. 'Pivotal-J ly coupled, to turnin horizontal plane, withthe forward apex end of said draft yoke "64,-is a draft'- `linlr 66. `Mounted in connection with the forward end ofsaiddraft-link are a pair of vgrooved "rolll ers 67-68 whichrespectively `engage Vopposite sides of'a transverse draft bar ewhich iscon,-`

nectedwith the rear end of a roller, tractor-or other hauling means bysuitable off-setting `brackets or frame supports 70.

In the use of the machine for preparing a subgrade upon which is to becast afirst'courser of concrete slabs, the forms" 18 are set to correctgrade along each 'side of the course.` The forms 18 being set, the"grading machine is mounted thereon so that the traction wheels v"17thereof ride on the tops of said forms, with the guide rollers 24adjusted to bearagainst. the inner faces'of the forms so `as to hold themachine against lateral displacementand so that the saine runs truealong the forms. The grading roller or other hauling. means is-nowcoupled through thefde-I' 'scribed draft appliances'with the machine;and

' the operator takes his'station ontheplatform 63 ready to control theoperations of the machine;V

3io. Y,

Ifgit is desired to'scarify the surface between the forms which'isgto'be graded,the operator manip# ulatestherhand'wheel42 'to lower thescarifying -means to operative position, whereby the teeth 3`2arebroughtlinto-"operative 'relation to the earth. If the Vscarifyingoperation is to be separately performed, the-scraping means is raised toinactive position;vr Itisfrequentlypossible to perform both"` thescarifying operation and the scraping operation at the same time, inwhich case the scraping meansis lowered'to a selected adjustedposition'acc'ording tothe depth of sub-j` grade desired. As the gradingroller or `other hauling meansV is moved'v forward, the trailing gradingmachine follows thereafter and is pulled v:straight and true through thedescribed ldraft coupling devices, any lateral deviation or off-set pathof travel ofthe grading roller orwhauling 1 means being automaticallycompensated for by corresponding "movement of the draft bar 69 betweenthe rollers? 67--68 of the draft linl; 66, so

that a constant straight pull withoutv Iateraldeviation "is transmittedto the gradingvmachine, and consequentlyl n o over turning pressure isexerted' by the guide rollers 24 on the forms 18. lThe scarier teeth 32will, as they are advanced, dig into the subsurface so as to'eiiicientlyloosen irc the'soil and breakdown high spots therein.' A*The downwardlyand `rearwardly inclined front plates 31 of the holder of 'thescarifierteeth will operate toi downwardly deflect loosened soil so thatthe same,` is passed rearwardlybetween theteeth and behindthe'scarifying means tov lie in front of the :scraping means; at thesame time any larger stones dislodged from the soil, and not capable offisc passing between the teeth 32, willfbe rolled ahead -along 'thesurface.' The operator can readily Y`manipulate the scarifying means toraise and .lower the samelasconditions'may require while *the machine isbeing advanced. Since thescr'apingfme'ans is rearward of the scarifyingmeans, the soil loosened by the latter lies inthe path of f the former,so that the toe-plate50 will scrape and spread the same evenly atlthetrue subgrade level, any excess soil being tumbled ahead'by the concavesurface ofthe scraper plate `48, until -the j accumulation `thereofbecomes suiiicient to be released, whereupon the'operator may actuatethehand wheels -54 to raise the scraper plate, and *thus deposit the excessaccumulated soil Tin one.'

place ready yfor removal; again lowering the` scraper plate `forcontinued `operation as thev machine proceeds. From the above it will beap- `parent .that scarifying, scrapingandrolling of 'the subgrade may beperformed in one operation, thereby saving lconsiderable time and labor.

If conditions warrantyhowever, either the scari-l fying or scrapingmeans may be alone employed atany-stage ofthe work.

In operating the machine preparatory to laying -a secondcouijse ofconcrete to abut or laterally adjoin a first laid courseythe forms `1SAat theV innerfside of Ytheifi'rstlaid course are removed,

andan outer run of forms are jerected-paralle'ling crete well .within orback. of itsedge, so as to avoid rislr of chipping such edgeQtherjournals of the traction wheels 17 are'reversible'in their bearings 16so that the same may be located on the exterior side of the chassis beaminstead of the inner side as shown in the drawings. When so reversed theftractionwheels 1'7 will bear on the top surface of thevfinished*concrete well ba'ckvfrom its edge,.

while the adjacent guiderollers 24 will neverthef less bear on theexposed side face of vthe laid conf described,

crete. slabs. The scarifying and scraping operations Vare thereuponcarried on inthe same manner as already described as the thus mountedgrading machine is advanced along the work.

romY the above description it willwbeV obvious that the level of themoving grading machine is determined by the set forms 18, andconsequently is constant relative to the forms. It therefore followsthat if the scraping blade isset to given depthV below the form tops,the produced subgrade will be accurately produced and iixed at suchdepth without variation therefrom. Not only will thel produced subgradebe uniformly run,A but the same'may be .predetermined by the setting ofthe scraping plate to the exact point desired. This is of greatimportance since it eliminates the waste consequent upon castingconcrete slabs of thicknesses inv excess-of contract specificationswhich lresults from excessive cutting down of subgrade levels, and whichfrequently occurs when subgrades are prepared by hand or b y machinesrunning on ground surface. It has been estimated Vthat'inlmost concreteroadkworkvthe nishedjslabs average over an eighth of an inch in excessof required specified thicknesses, for whichr excess the contractorreceives no compensation although 'being penalized for deficientthicknesses. An excess of an eighth of an inch in Va twenty foot roadwould consume about 4l cubic yards of concrete per mile, whichrat anaverage cost ofv approximately six dollars per yard would involve a lossof nearly $250.00, per mile f The vsaving of this lossalone illustratesthe advantages vto 'be gained byy accurate subgrading as 4it can b eaccomplished by the novel construction of gradingmachine according tothis invention as above As a further part ofthe instant invention meansAare provided for facilitating vthe transportation of the novel gradingmachineV from place to Vplace where its use isv required. To` this endthere provided'a pair of detachable journal brackets adapted to beaffixed to and intermediate the ends of the exterior bolster beams11-12,

` upon which may be rotatably mounted transport tractionwheels 7l formovablysupporting the machine so that it can be towed'from place. toplace. Each such journal bracket comprises a clip-plate 72 :havingannndeicut rib 73 at onev side. rlrhis clipplate is disposed under abolster Abeam with said rib 7.3 hooked over. the bottom flange` at theinner side of the beam. Integral with said clip-plate '72 is boss74'from which-proa jects a journal'portio'n '75 to receive the hub ofthe tractionY wheelV '71. Bolts '76? are Vpassed through said clipeplateand boss with their heads overlapping thebottom flange of thebolsterbearn at the Outer Sidr thereof Integral with, and" eX- ingsshallbe interpreted as illustrative and not in a limiting sense.

I claim :--v

' l. Ina machine for subgrading between preparatory to 'casting concretepavingslabs, a

frame-work having traction means to vride'on f said forms, a scarifyingmeans vertically movable' in connectionwith said frame-work to ac-I tiveor inactive positions, pivoted lever arms lfor Alowering and raisingsaid scarifying1me`ans,

means for actuating said lever arms, and verticallyadjustable stopscrews mounted on said frame-'work to lie in the path of said lever armsand adapted .to Vvstoppdownwardmovement there-A ofY to therebyselectively limit the active position level of said scarifyingmeans. 2.A machine for subgrading between forms preparatory to casting concreteVpaving slabs,

comprising a frame-werk having tractionwheels' toother edge of saidscarifyingmeans for operar tion at a predetermined depth below the topsof said forms, a manipulatable scraping member adjacent to the rearwardend of said machine-tol extend transversely substantially throughouttheAspace between said forms, and adjustable means to selectively.positionthe effective scraping edge of said scraping memberffor operation atapredetermined depth below the tops of said forms.` H3. A machine forsubgrading between forms preparatory to casting concrete pavingV.slabs,'

'comprising a frame-work having tractionwheels to .ride on the tops ofsaid forms, guide rollersmountedy in connection with said frame-work Vtobear laterally aainst side Vfaces of vsaid forms, 1

a manipulatable toothed scarifying means adjacent to theforward end ofsaidframe-Work-to extend transversely between said forms,.adjustk.ablemeans to selectively position the effective toothed edge of saidscarifying meansfor opera.e

able means to selectively position the effective'k s.

scraping edge of said scraping member for operation at a predetermineddepth* belowthe tops of said forms, and means Vaccessiblevat the rear.end of said frame-work for selectively manipulat- .ing said scarifyingmeans and said scraping membsratwill?. j v 4, In a machine forsubgrading between forms preparatory to casting concrete paving slabs, a

frame-Work having traction wheels to ride on the l tops of said forms,guide rollers mounted in connection with said frame-work to bearlateral- 1y against Side.; faces @mais forms and.

lll-5 to adjust said faces. i. `5. In a `machine for subgrading betweenforms preparatory to casting` concrete pavingslabs, a

Vfname- Work having traction wheels to ride on the 4tops of said forms,said frame-work having rotatively adjustable dependent shafts', guide i*rollers at the lower portions of said shafts, said shafts having meansto laterally shiftjthe same when -rotatively adjusted to dispose saidguide rollers toeengage side faces ofsaid formaandI means to fix saidshafts in given` laterally adv'- justed positions. w l

6. In a machine forsubgrading between forms preparatory to castingconcrete paving slabs., a: `frame-work having traction wheels to ride onthe tops of said forms, saidframe-work rotatively adjustable dependentShaftag'uide-rollers having anti-friction bearings mounted on. the lowerportionsof said shafts, said shaftshavingl eccentric portions, saidframe-work having seats to receive said eccentric portions, and meansAto` Y, secure said shaftsv in given'rotatively adjusted positionswhereby said guide `rollers -are 'dispos ed to engage side faces of saidlforms.` Y

f7.. In a machine for subgrading betweenforrns preparatory to castingconcrete paving s1abs, a frame-work having bearing portions onitsppposite longitudinal sides, and `traction wheels having `journalmembers mountedin said bearing portions, said traction wheels andvjournal mem? bers being reversibly relative to said bearing por-VVtions to selectively dispose said traction wheelsv at either the inneror outer ends of said bearing portions, said traction wheels beingadapted to ride on the tops of said forms to movably'su'pport themachine in bridgingrelation across the same. Y Y

y 8. I n a machine for subgrading between forms preparatory to'castingconcrete paving slabs, a

carriage to travel on the tops` of said forms in bridging relationthereto, means to retain saidv carriage against lateral `displacementrelative toV said for1ns,"a` scarifyingmeans-mounted on saidr carriageto extend between saidforms, means to raise and lower saidscarifyingmeans to inactive oractive position, and means to selectively positionsaid scarifying means for operation at a predetermined depthbelowtlietops of said forms, said scarifying meansv including a holderof Vf shaped cross-section, a Vplurality of downwardly v y and forwardlyinclined laterally spaced scarifying teeth Aprojecting from said holder,and the upwardly andrforwardly inclined face of said A guide rollersrelative tovsaidform ened soil relativelylarge stones and rubble. i

9. In a machine for subgrading `between formsA holder serving to defiectloosened soil rearwardly v a through spaces between saidteethwhileoperatf, ing to roll forward and separate from 4said loos- 'fpreparatory'` to casting concrete paving slabs,a``V

jcarriage to travel on the` tops o f said .forms Vbridging"relationthereto, means to retain said carriage against lateraldisplacementivrelative to v said forms, a scarifying means mounted o nsaid 7 carriage to extend between said forms, means-*tol raise and lower.saids'carifying means to inactive predetermined depth below the topsVvof said 1 frames, said scarifying meansinclnding a holder of Vfshapedcross-section, apluralitygoflaterally preparatory tocasting concretepaving slabs,

' or active position, and means to selectivelyposi-` tion saidscarifying means foroperation at av 100i carriage to' travel on' thetops of said forms inl,`

bridging relationthereto, means to retain said;V carriage againstlateral `displacementrelative to Y said forms,` said'tcarriage having `aplatform forV `st ationing an operator at its rearward end, a `sc'ariermeans at the forwardend portion of said carriage comprising a holder toextend bei,

tween vsaid` forms having a' plurality off downwardly andangularlydirected laterally spaced scarirler teeth, means on Vsaid carriage toraise -and lower said scarier means including apower shaft andvhand-'wheel accessiblefromfsaid rear` A platform, adjustable stop meansfor predeterminf ki ing the working level of said scarifier means," a15.

scrapingl means at the rearward endlportion of said carriage comprisinga concave-convex scraper plate to rextendbetween, said forms hav-` ingal sharpened toefplate atfits lower margin,

i means `on said carriage to lraise Aand lower said scraperA plateincluding independentlymovablefv 'carrying' means connected respectivelywith'gop-z positev end portions of said` scraper j plate and powershafts for respectively 'actuating said' car` f rying means `eachfhavinga hand-'wheel' accessible from Asaid rear platform, and adjustable. stopmeans for predeterminingv the working level v of saidscraper plate.

so, i

